Thin films of relaxor ferroelectric/antiferroelectric heterolayered structure for energy storage

We report the energy-storage performance and electric breakdown field of antiferroelectric PbZrO3 (PZ) and relaxor ferroelectric Pb0.9La0.1(Zr0.52Ti0.48)O3 (PLZT) single films, as well as PLZT/PZ and PZ/PLZT heterolayered films grown on SrRuO3/Ca2Nb3O10-nanosheet/Si substrates using pulsed laser deposition. These films show the highly textured (001) orientation. The 'square' hysteresis loop with very sharp electric field-induced antiferroelectric-ferroelectric (AFE-FE) phase transition is observed for the PZ/Si film, meanwhile the heterolayerd PLZT/PZ/Si and PZ/PLZT/Si films show the 'slanted' hysteresis loops with gradual phase transition. Moreover, the electric field-induced AFE-FE phase transition in the hererolayered films is occurred at lower applied electric fields (~275 kV/cm) than that in the PZ/Si (~425 kV/cm), due to the presence of the PLZT layers in the heterolayered films. Owing to the dense structure in PLZT layer, the large electric breakdown strength of 2000 and 1825 kV/cm, and then the high recoverable energy-storage density of 28.8 and 23.8 J/cm3, respectively, are obtained for the PLZT/Si and PZ/PLZT/Si films.